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-53- CWI retained the services of Merrick and Company and Geo-Hydro Consultants, Inc. to investigate the slope stability of the entire surface facilities area at the Orchard Valley mine. Phase I of this study was completed and a summary report, prepared by Geo-Hydro Consultants, Inc. was submitted to the Division for review on July 21, 1981. The analysis, prepared in accordance with the present state-of-the-art of geotechnical analysis, determined that no immediate major hazards existed at the mine site. The report does observe, however, that some local stability problems exist and the factors of safety of individual cuts and fills will have to be increased by redesign and reconstruction to achieve a stable final reclaimed configuration, in accordance with the regulations. CWI's geotechnical consultants, Geo-Hydro, Consultants, Inc., completed the Phase II analyses on April 15, 1982, in accordance with the stipulated requirements of the originally approved Permit. The stipulated tasks of the Phase II analyses included: Evaluation of nearby landslides mapped by the Colorado Geological Survey; completion of test drilling and test pits; installation of monitor wells; soil and rock testing; and the completion of a series of stability analyses for current slope configurations of the existing surface facility area at the Orchard Yalley mine. CWI, in conformance with recommendations made by its geotechnical consultants, has installed sophisticated tilt-metering devices within several of the fill benches which exist within the surface facilities at the Orchard Valley mine. The purpose of these devices is to collect additional geotechnical data with which to verify past analytical assumptions and with which to complete final analysis and design, originally stipulated as Phase III of the surface facility studies, within the approved original Permit. Utilizing the results of Geo-Hydro, Consultants, Inc.'s analyses, Merrick & Company, Inc., design consultant to CWI, completed a Phase II amended design for the drainage facilities at the existing surface facility area of the Orchard Yalley mine. CWI has also completed a detailed stability analysis and redesign of the proposed final reclaimed configuration for the surface facilities at the mine. The study and the configuration have been approved by the Division. In August, 1986, CWI submitted a permit revision application to construct a new west portal facility in the East Roatcap Creek valley at the Orchard Valley Mine. This application proposed the construction of a new portal facility and haul road, because the existing portals at the Orchard Valley Mine had been rendered unuseable by an underground coal mine. The applicant proposed to upgrade an existing public access road to serve as a coal haul road to the proposed west portal bench, which will be constructed by a balanced cut and fill method. The portal bench fill includes a 130 foot maximum height terraced earthen fill, to be constructed across East Roatcap Creek. Maximum interterrace facial slopes shall not exceed 2.5h:1.Ov (horizontal to vertical) slope gradient. A 48 inch concrete culvert will be installed beneath the cross valley fill to accommodate the 100 year flow of the East Roatcap Creek.